Interdisciplinary Program in Biomechanics and Movement Sciences, Department of Physical Therapy, University of Delaware, Newark, Delaware, USA.
J Orthop Res. 2012 Mar;30(3):377-83. doi: 10.1002/jor.21544. Epub 2011 Sep 7.
It is important to know the magnitude and patterns of joint loading in people with knee osteoarthritis (OA), since altered loads are implicated in onset and progression of the disease. We used an EMG-driven forward dynamics model to estimate joint loads during walking in a subject with knee OA and a healthy control subject. Kinematic, kinetic, and surface EMG data were used to predict muscle forces using a Hill-type muscle model. The muscle forces were used to balance the frontal plane moment to obtain medial and lateral condylar loads. Loads were normalized to body weight (BWs) and the mean of three trials taken. The OA subject had greater medial and lower lateral loads compared to the control subject. Seventy-five to 80% of the total load was borne on the medial compartment in the control subject, compared to 90-95% in the OA subject. In fact, complete lateral unloading occurred during midstance for the OA subject. Loading for the healthy subject was consistent with the data from instrumented knee studies. In the future, the model can be used to analyze the impact of various interventions to reduce the loads on the medial compartment in people with knee OA.
了解膝关节骨关节炎（OA）患者的关节负荷程度和模式非常重要，因为改变的负荷与疾病的发生和进展有关。我们使用肌电图驱动的正向动力学模型来估计膝关节 OA 患者和健康对照者在行走时的关节负荷。运动学、动力学和表面肌电图数据用于使用 Hill 型肌肉模型预测肌肉力量。肌肉力量用于平衡额状面力矩，以获得内侧和外侧髁负荷。负荷被归一化为体重（BW），并取三个试验的平均值。OA 患者的内侧和外侧下负荷明显大于对照组。在对照组中，75%至 80%的总负荷由内侧间室承担，而在 OA 患者中则为 90%至 95%。实际上，OA 患者在中期完全出现外侧卸载。健康受试者的负荷与仪器测量的膝关节研究数据一致。将来，该模型可用于分析各种干预措施对降低膝关节 OA 患者内侧间室负荷的影响。
